Pocket level



E\ G. D. HAM/:SENI

Feb. 27., 1923.

POCKET LEVEL.

2 sHEETs-sHEE'T 1.

FILED SEPT. 24 1920.

.gil

Patented Feb. Z7, 1923.

POCKET LEVEL.

Application ledeptember 24, 192D. 'Se 1a1`1\1'o. 412,595.

To LZ'Z whom may concern Be Vit known, that I, 'ENniQUn G. Don-R-INGHARIvrsEN, a Citizen off Peru, residing at H aeienda Sausal, via.Trujillo, "Peru, `South America, have `invented certain new landusefulllmprovements inl 'Pocket Levels, ot' which the following is aspeeiieation.

This invention relates toa comb-ined level and angle measuringinstrument so Con'- structed that the raft-S may be folded into compact`toxin for easy ltransp ortation and which, at the saine time, affordsthe same degree of 'accuracy when in operation as may be obtained 'bythe useioi heavier and more 1- complieated instruments.

This invention further relates to improvements inthe type oiinstrumentdisclosed in my eo-pen'ding applieetion Serial No. ;lZf, filedSept. j2i,f1920, said improvements beings, ,cted more' particularly. tothe mountingof :the various parts so Vthat horizontal Yer-tical anglesmuy 'be read with sgi-rd to 'the peint @ver which the l'- pod earryng'the instrumentpositioned This invention a'lfso proifides an improvedsighting device v the for-m of a' prism niountejdin'a recessloi apivoted arm.

Othery advantageous features of the invention `,\v'ill 'be apparent uponretereneeto .the ,Speeiiieationivliieh refers tothe accompany :iisgdrawings lIn the drawings r- Figure 1represents a ,top plan view of theassembled device With-'apart in SP/@tion i0 a5 disclose the tripod pvotPili; 1

Fig-.ure .2 ,iS i seetion ,on the lineQ-Q of Figure l, looking iii thedirection 0f the :@iflOWS Figure 3 is a, section on the line 3 3, Fig-4'0 111e lflooking in the direction of the arrows;

bled device showing "the movable arm in several ppsitionss device infoled Qsitien.

" 'Theiiumerel 1 designates af0lli1iginiem- She t e.. formelcirdelsrfaduat, 360.;` A Sshoiviihet Remember marie tu@ parte .dividedeliig the line @iid diese parts 'are preferably le sed, the hinges beingShown diagramdOttsdgliues et 114 ?Fieille 1- Eaeli ofthe .we parte ofthemenih met" fthe "length 0f 'Q 55 fiftht endthese ilotbles 9i the `the:23 is" termed; ,d

their-.e eed @i the Jaim'. :23.11

two parts are adapt-edfto "embrace a pivot pin 13 attached to atripod orlothersuitable support (not shown). it Will-be understood ,that clampingmeansinoty shoivn) v'may be provided Vfor clampingfthe member 10`in anybe provided for adjust-ing thehorizo-ntalposition ot themember '10or'tripod sotha-t'the i member 10 will be level `whenth'e1instrumen'tis'in operation. l

A base 14 is provided with an enlarged end 15 preferably circula-r inStorm, saidend being formed With a recess adapted to receive the upperend ot' tlie'pivot 13 oi 4the tripod A lrecess 1G'is formed inoneedge of`jthebase 1 4 and thevertical'side wall 17 .of

upper extremities in order to receive suit# able fastening devicestoitseeuring the base 14e to a. support when it 'is 'used ,independentl7of the ,circular ,member 10. .l

An arm 23 is pivotally mounted to .the ien- V larged portion 15ottliebase .bymeanseta threaded y,pivot 24, the axis .Oft which is inthe same plane and perpendicular@ the axis of the pivot pin13'otthetripod. 'The arm Ai243 is provided lat one .endfivith arent-rally projecting' eireular lport-ion Qlthat ,engeges 'the pivot-24. The armniay 'be turnedfabout the pivot 2li and -is retained iii.adjusted -p- Stfm by means of the nu@ 2e which bind or releaser the1.11m in the Wein known.

-manner- V The ,arm is alsol .provided With-recesses ,adapted .to,receive a. ,domi-poss ease 29, which is adiustably seen-redin theeasing bythe threaded stud, v27, `and also y oplei/:el tbatv `is*preferably inserted the arm lower side thereof retain nreiefitingshoulders." retaf @11d tasteningidevices l31, ne

proieeting portion'liiayvin an face inclined aitthe saine-a le as feceet the ibasehe adjusted positionand .also `that mealngafmay i away at34, the recess being terminated by the member 35 which forms acontinuation of the body of the arm. A strip 36 is secured to portion 35of the arm by means of suitable fastening devices 37 and is formed atone extremity with a boss 3S preferably internally threaded so as toreceive a thumb screw 39 adapted to be inserted through a slot in thegraduated arc-shaped member, as will hereinafter appear.

A graduated arc-shaped member 40 is pivoted at one end to the base 14preferably at the surface 19 of the end recess by means of a threadedstud 41 and adjusting nut 41 engaging the same for the purpose ofreleasing or binding the graduated arm 4U so that it may be placed ineither operative or folded position. The arc-shaped member 40 is alsoprovided with a longitudinal arcuate slot 42 through which the screw 39may be inserted.

The projecting portion 33 of the arm 23 is recessed at one side, asabove described, and in this recess 34 is inserted a prismsightpreferably composed of glass plates 44 and 45 and a silvered refiectingsurface 46. It will be understood that the plates 44 and 45 havecross-lines marked or etched thereon, as shown in Figure 1. A slottedpointer 461l also secured to the projecting portion of the arm 23cooperates with the arc-shaped member 40 to indicate the inclination ofsaid arm. The base 14 has an angular cut 48 near one end, and the pro-vjectlng portion 33 of the arm also has a slot 47 cut therein at acorresponding angle in order to provide clearance so that the arm 40,when thumb-screw 39 is temporarily removed, may be folded into compactrelation with the other parts of the device.

lt will be noted that the axes of the pivot 24 and the vertical pivotpin 13 of the tripod are in the same vertical plane and at a right angleto one another and also that the point of intersection of thecross-lines of the plate 45 is in the same plane with the horizontalaxis of the pivot 24 and with the indicating surface of the pointer 46.lt will also be noted that the indica-ting surface 17 of the base is inthe same vertical plane as the axis of the pivot pin 13 of the tripod,This construction enables the measurements of vertical and horizontalangles to be both referred to the point over whichthe tripod ispositioned. ln reading vertical angles the object is sighted through theprism side plates and the arm is adjusted in position until the imageappears symmetrically about the intersecting points of the cross-lines,when the arm mav be secured in positionvby means of the adjustable nut26 and the angular inclination indicated by the position of the pointer46a on the graduated forward face of the arcshaped-member 40. Theopposite side of the arc-shaped member 40 is preferablyr graduated intonatural sines so that the sine of the angle of inclination may also bereadily obtained. in reading horizontal angles the objects are sightedthrough the prism sight 43 in the same manner, pivot arm 23 being firstmoved to closed position, in which position it should be level asindicated by the level on the arm 23. The readings on the member 10corresponding to the positions of the vertical surface 17 will indicatethe horizontal angle lbetween the objects sighted.

To fold the parts for. easy transportation, the base and circular memberare removed from the pivot of the tipod after whichy the two sections ofthe circular member mayfbe folded into contact about their hingedconnection. The thumb-screw 39 may be removed and the arm and arc-shapedmember folded tothe relative positions shown in F ig. 5. The screw 39can then be inserted through the opposite side of lug 38 or keptconveniently in a case provided to receive the folded instrument.r i

I claim :M

1. In an angle measuring instrument adapted to be used with a tripodhaving a vertical pivot pin, a foldable member mounted at its centerabout said pin, a base mounted on said pivot pin and'superposed on saidmember, an arm, ahorizontal pivot for said arm at one end of said basewith its axis in the same vertical plane with and at a right angle tothe axis of said pivot pin` a graduated arc-shaped element pivotallymounted at ythe other endof said base, and a pointer carried by the freeend of said arm and cooperating with said `graduated element forindicating the inclination of said arm, the indicating surface of saidpointer being in the same plane with thek axis of said horizontal pivot,said base having a vertical wall in a. vertical plane with the axis ofsaid pivot pin and cooperating with graduations on said member wherebyhorizontal and vertical angles may be 1roneasured with respect to thecenter of said ase.

2. In an angle measuring instrument, `a

base having a recess formed therein, an arm having a projection adaptedto t into said recess, means for pivotally connecting said arm to saidbase adjacent one end of the latter, said arm having a recess in saidprojection. a right angle prism mounted in said recess, the incident andemergent surfaces of said prism having cross-lines marked thereon, apointer ycarried by the free end of said arm, a graduated arcshapedelement detachably carried by said base adjacent its opposite end withwhich said element said pointer cooperates to indicate the inclinationof said arm, the indicating surface. of said pointer, the point ofintersection of the cross lines on the incident surface of said prism,and the axis of said pivot being in the same plane.

3. In an angle measuring instrument adapted to be used with a tripodhaving a vertical pivot pin, a graduated member having an aperture toreceive saidpin, a base pivot-ally mounted at one end on said pin, anarm, means for mounting said arm for swinging movement at said end ofthe base, said means having a horizontal axis, a right angle prismcarried by the free end of said arm having its incident and emergentsurfaces marked with cross-lines, the point of intersection of thecross-lines on said incident surface being in the same plane with saidhorizontal axis and in a vertical plane containing the axis of saidpivot pin, and means carried by said base and associated with said armfor indicating the inclination of the arm, said base having anindicating means cooperating With said graduated member for indicatingthe horizontal angular position thereof.

il. In combination, a base adapted to be mounted for movement in a.horizontal plane, an arm connected to said base adjacent one end of thelatter for movement in a vertical plane, the axes of movement of saidbase and arm. lying in vertical relation to one another, a graduatedarc-shaped element carried by the other end of said base, said elementhaving an arc-shaped slot extending longitudinally thereof, a stripcarried by the free end of said arm, and means adjustably engaging saidstrip and passing through said slot for securing said arm in adjustedposition.

5. In combination, a circular member, a base, an arm mounted on saidbase for swinging movement, the axis of movement of said arm lying abovethe center of said member, an aro-shaped element carried by the base andfoldable against the latter, said arc-shaped element adapted, when inoperative position, to indicate the inclination of said arm, and asighting prism supportedA 6. In combination,v a foldable member havinga. central hole to receive a vertical pivot pin, a base pivotallymounted on said v pin and superimposed 0n said member, an arm, ahorizontal pivot for mounting said arm on said base to permit said armto be folded into contact with the upper surface of the base, a sightingprism carried by said arm having-cross-lines on its incident and yemergent surfaces, a graduated arc-shaped element pivoted to said base,a pointer carried by said arm and associated with said gjraduatedarc-shaped element, and indlicating means on sald base, one of thecrosslines of said incident surface being in the same plane with saidindicating means and the axis of said vertical pivot, and the othercross-line being in the same plane with the indicating surface of saidpointer and the axis of said horizontal pivot.

7. In combination, a foldable graduated member adapted to be mounted ona tripod, a base pivotally mounted on the said member, an arm pivotallymounted on said base with its pivotal axis lying above the pivot of saidbase on said foldable member and said arm being adapted to be foldedinto contact with the upper surface of said base, an arc-shapedgraduated element vvalso pivotally secured to the base and adapted to befolded into contact therewith, and a level and sighting prism carried bysaid arm.

In testimony whereof I have hereunto set my hand inl presence of twosubscribingwitnesses.

ENRIQUE G. DOERING HARMSN. 4

Witnesses:

C. GUELDIz, C. M. LIAvEz'r.

